1. Field of the Invention
The present invention relates to a disk apparatus, and more particularly to a disk apparatus in which the in-and-out movement of a disk tray for carrying a disk into a home position within a housing or out of the housing is guided by a guide mechanism having the guide ways provided on the disk tray and the position regulating pieces provided on the housing.
2. Description of the Related Art
FIG. 5 is a schematic plan view of a conventional example of a disk apparatus of this kind. In this disk apparatus, a disk tray 1 has disk loading faces 11 and 12 on which a small diameter disk and a large diameter disk are alternatively loaded, whereby the disk (not shown) loaded on any one of them is carried into the home position within a housing 2 or out of the housing 2. Also, the guide mechanisms 3 for guiding the in-and-out movement of the disk tray 1 into or out of the housing 2 are provided. The guide mechanisms 3 include the guide ways 31, 31 that are left and right parallel flat planes provided in the disk tray 1 and extending straightly in the direction where the disk tray 1 is moved in or out (back and forth direction), one pair of fore position regulating pieces 32, 32 like projections disposed oppositely to the left and right on the fore part of the housing 2, and one pair of rear position regulating pieces 33, 33 like projections disposed oppositely to the left and right on the rear part of the housing 2. Also, a guide groove portion 34 provided on the back side of the disk tray 1 and extending in the back and forth direction, and a guide projection 35 provided on the housing 2 and slidably fitted into the guide groove portion 34 are provided, as shown in FIG. 6, which is an enlarged view of a portion taken along the VI-VI line of FIG. 5.
And one pair of fore position regulating pieces 32, 32, left and right, are located on both sides of the disk tray 1 across the left and right guide ways 31, 31 when the disk tray 1 completes carrying the disk into the housing 2, the opposed interval W1 between them being slightly wider than the mutual interval L between the left and right guide ways 31, 31, as shown in greater scale in FIG. 7. Also, the one pair of rear position regulating pieces 33, 33, left and right, are formed in the same way as the fore position regulating pieces 32, 32, the opposed interval between one pair of rear position regulating pieces 33, 33, left and right, being identical to the opposed interval W1 between one pair of fore position regulating pieces 32, 32, left and right, and slightly wider than the mutual interval L between the left and right guide ways 31, 31, as shown in FIG. 5. The opposed interval W1 between the left and right fore position regulating pieces 32, 32, or the opposed interval between the left and right rear position regulating pieces 33, 33, and the mutual interval between the left and right guide ways 31, 31 for the disk tray 1 are defined in the above relation, thereby making loose the guide action by the guide mechanism 3, because it is necessary to suppress the load required to drive the disk tray 1 to carry in or out the disk and arrange the disk at the home position inside the housing 2 without great misregistration at the time of completing carrying in or out the disk.
Moreover, the anti-slip lugs 13, 13 are provided to the left and right in the fore end part of the disk tray 1, as shown in FIG. 5 or 7. The anti-slip lugs 13 have a function of preventing the disk tray 1 from slipping out of the housing 2 by engaging the left and right stoppers (not shown) included at the rear end portions of the housing 2. In the disk apparatus as illustrated, the anti-slip lugs 13, 13 are disposed opposite to the left and right sidewall inner faces 21, 21 for the housing 2.
On the other hand, the in-and-out movement of the disk tray 1 into or out of the housing 2 is performed by a rack 41 provided on the back side of the disk tray 1 and a pinion 42 having a motor (not shown) installed on the housing 2 as a drive source, in which the pinion 42 is meshed with the rack 41.
In this conventional disk apparatus, after the disk loading is performed by enabling the disk tray 1 that is loaded with the disk at a retreated position to carry the disk into the home position inside the housing 2, the disk is passed at the home position from the disk tray 1 to a turntable, not shown, and rotated together with the turntable so that an optical pickup, not shown, scans the disk face to perform the recording or reproduction. Also, after the disk is passed from the turntable to the disk tray 1, the disk tray 1 carries the disk out of the housing to perform the disk unloading.
In the disk tray 1 for performing the disk loading in the above way, it is required that the disk loaded on the disk tray 1 may be aligned with the turntable within a permissible range at the time of completing carrying the disk into the inside of the housing 2. If the precision of alignment is low, the disk maybe passed from the disk tray to the turntable incorrectly, thereby degrading the performance of subsequent recording or reproduction, or making the recording or reproduction difficult to cause various troubles.
On the other hand, as a prior example, it is well known that the guide mechanism for guiding the in-and-out movement of the disk tray is formed by slidably fitting the end portion of the disk tray into the guide groove formed in a base chassis as the housing (e.g., refer to JP-A-11-328801). Also, to make the in-and-out movement of the disk tray smoother, it is well known that the disk tray is obliquely moved at will (e.g., refer to JP-A-5-266563).
However, in the conventional disk apparatus as shown in FIGS. 5 to 7, if the guiding operation of the guide mechanism 3 is loose as described above, a situation may occur that the disk tray 1 guided by the guide mechanism 3 is moved obliquely to carry the disk into the housing 2. Particularly, when a rotational drive force of the pinion 41 is transmitted to one portion of the rack 41 provided at a biased position on the back side of the disk tray 1, the disk tray 1 loosely guided by the guide mechanism 3 inclined to the left or right may be moved (obliquely) toward the inside of the housing 2, so that the disk tray 1 is kept inclined at the time of completing carrying in the disk, as shown in FIG. 5. In this way, if the disk tray 1 is kept inclined at the time of completing carrying in the disk, a problem arises that the alignment precision of the disk is degraded due to some cause and the disk is incorrectly passed from the disk tray to the turntable, even though the looseness of the guide mechanism 3 is decided to the extent of suppressing the load required to drive the disk tray 1 to carry in or out the disk and arranging the disk at the home position inside the housing 2 without great misregistration at the time of completing carrying in the disk.
In this respect, the above-cited prior example involves a technique that the guide mechanism loosely guides the disk tray simply, or a technique that the disk tray is obliquely moved at will, and can not solve the above-mentioned problems.